HOWTO

Now when you have CollectD and InfluxDB installed you may configure Grafana 😃 First configure repo with current Grafana version (select your distro): curl https://packagecloud.io/gpg.key | sudo apt-key add - deb https://packagecloud.io/grafana/testing/debian/ wheezy main Now install package (on wheezy I needed to install apt-transport-https to allow installation of packages from repo via HTTPS): apt-get update apt-get install -y apt-transport-https apt-get install -y grafana By default Grafana will use sqlite database to keep information about users, etc: ...

I wanted/needed some statistics on few my machines. I saw earlier grafana and was impressed so this was starting point. Then I started reading about graphite, carbon and whisper, and then… I found InfluxDB. Project is young but looks promising. Let’s start! On project page there is no info about repo but it’s available, configure it: curl -sL https://repos.influxdata.com/influxdb.key | apt-key add - echo "deb https://repos.influxdata.com/debian wheezy stable" > /etc/apt.sources.list.d/influxdb.conf for Ubuntu use url like (of course selecting your version): ...

I wanted/needed some statistics on few my machines. I saw earlier grafana and was impressed so this was starting point. Then I started reading about graphite, carbon and whisper, and then… I found InfluxDB. Project is young but looks promising. Installation of collectd is easy on Debian because packages are in default repo. One problem is that packages may be old, ex. on wheezy it version 5.1. But in backports/backports-sloppy you may find current 5.5, so enable backports first: ...

From the first moment I heard about Let’s Encrypt I liked it and wanted to use it as fast as possible. But the more I read how they want to implement it, the more I dislike it. Current project with automatic configuration is not what I want to use at all. I have many very complicated configs and I do not trust such tools enough to use them. I like UNIX’s single purpose principle, tools should do one thing and do it well - nothing more. ...

Lately I had a lot of brute force attacks on my WordPress blog. I used basic auth to /wp-admin part in nginx configuration to block this and as a better solution I wan’t to block source IPs at all on firewall. To do this, place this filter code in /etc/fail2ban/filter.d/wp-login.conf: # WordPress brute force wp-login.php filter: # # Block IPs trying to authenticate in WordPress blog # # Matches e.g. # 178.218.54.109 - - [31/Dec/2015:10:39:34 +0100] "POST /wp-login.php HTTP/1.1" 401 188 "-" "Mozilla/5.0 (Windows NT 6.0; rv:34.0) Gecko/20100101 Firefox/34.0" # [Definition] failregex = ^<HOST> .* "POST /wp-login.php ignoreregex = Then edit your /etc/fail2ban/jail.local and add: ...

I have some Ansible roles to configure my vps, Raspberry Pi, etc. I like to test them before I broke something on my real, not clustered machines - I use Vagrant for that. But with it I had one problem - in playbooks I define hosts as groups of severs ex. web for my vps: Example Ansible playbook - hosts: web gather_facts: True sudo: True ... But testing machine wasn’t in this group and when I run vagrant I could only see: ...

Normally you want dynamic content to be fresh and not catchable. But sometimes it may be useful to cache it, like when you have website behind reverse proxy. To do this try something like this: <filesmatch "\.(php|cgi|pl)$"> Header unset Pragma Header unset Expires Header set Cache-Control "max-age=3600, public" </filesmatch> Sources http://www.askapache.com/htaccess/speed-up-your-site-with-caching-and-cache-control.html  external link

It will happen from time to time, that you’re on alien machine and have to brutally update things in db without knowing credentials. Example is for root (quite secure candidate to change because it shouldn’t be used in app 😃 ) but will work for any user. shutdown db service mysql stop create text file with command like this (update user accordingly) ex. in /tmp/pwchange.txt SET PASSWORD FOR "root"@"localhost" = PASSWORD("HereYourNewPassword"); start mysqld with --init-file param mysqld_safe --init-file=/tmp/pwchange.txt sometimes you may require to point configuration file ex. --defaults-file=/etc/mysql/my.cnf ...

I hate movies recorded on phone in vertical position. This just short tip how I dealt with with it last time: for m in *.mp4 do avconv -i $m -vf "transpose=1" -codec:a copy -codec:v libx264 -preset slow -crf 23 rotated-$m done Other examples: http://stackoverflow.com/questions/3937387/rotating-videos-with-ffmpeg  external link http://superuser.com/questions/578321/how-to-flip-a-video-180  external link °-vertical-upside-down-with-ffmpeg ...

I had some passwords saved in remmina but like it always happen, I wasn’t been able to remember them when needed. Trying to restore them I found that they’re encrypted in .remmina directory. Then I used this script to decrypt them 1: Extract script import base64 from Crypto.Cipher import DES3 secret = base64.decodestring("<STRING FROM remmina.prefs>") password = base64.decodestring("<STRING FROM XXXXXXX.remmina>") print DES3.new(secret[:24], DES3.MODE_CBC, secret[24:]).decrypt(password) http://askubuntu.com/questions/290824/how-to-extract-saved-password-from-remmina  external link  ↩︎ ...